• PiperForum.com is a vibrant community of Piper owners and pilots. Our over 1,500+ active members use Piper Forum to swap technical knowledge, plan meetups and sell planes/parts. We host technical knowledge of general aviation topics and specific topics on J3-Cubs, Cherokees, Comanches, Pacers and more. In addition to an instant community of pilots for you, PiperForum.com is a library of technical topics, airplane builds, images, technical manuals, technical documents and more.

    Access to PiperForum.com is subscription based. Subscriptions are only $49.99/year or $6.99/month to gain access to this great community and unmatched library of Piper knowledge.

    Click Here to Become a Subscribing Member and Access PiperForum.com in Full!

Wide open throttle vs stopping the prop during glide

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Nov 16, 2020
Messages
62
Reaction score
25
I read "The Engine-Out Glide" article in the last August issue of Aviation Safety magazine. There was a sidebar in the article about stopping the prop bringing an 8% improvement in glide distance. Many years ago, I took the GAMI Advanced Pilot Course. In that course, there was a discussion that it’s best to move the throttle to the wide-open position during engine-out glide. No one ever mentions this in the press, nor do I see it in piston aircraft emergency procedures. If you think about it, a windmilling engine is sucking air against a barrier when the throttle is closed. This is why "compression braking" works in non-diesel cars. I’m not going to do the experiment, but I wonder whether most or all of that 8% advantage can be had (for fixed-pitch props I think) by simply opening the throttle fully without having to attempt to stop the prop. This advice would hold for constant-speed props as well if oil pressure loss positioned the prop in fine pitch. Even in coarse pitch, the engine is still windmilling.

Steve
 

Latest posts

Back
Top